Compiz reached version 0.8.6 a while back - version which brings bug fixes as well as support for KDE 4.4 - but the version in Ubuntu 10.04 Lucid Lynx is still 0.8.4 so if you want to upgrade to Compiz 0.8.6, you can add the following PPA:
sudo add-apt-repository ppa:dashua/libcompizconfig && sudo apt-get update
sudo apt-get upgradeIf you're using Ubuntu 10.10 Mavrick Meerkat (still in alpha) already, it means you like testing. However, at the time of writing this post, Compiz in Ubuntu 10.10 is still 0.8.4 so you could install the latest Compiz 0.9 beta - the complete re-write of Compiz in C++:
sudo add-apt-repository ppa:amaranth/compiz && sudo apt-get update
sudo apt-get dist-upgradeNote: I've only tested Compiz 0.8.6 for Lucid.
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